How to make my OCR faster

I don’t have enough knowledge with MODI, but it is most likely that the pages you are loading are large (width & height) in pixels.
However, you should try LEADTOOLS, which handles PDF files and OCR images in a professional and a faster way.
Using LEADTOOLS the code is as simple as this:
In addition, they have cloud services that you can use instead of creating your own application.
https://services.leadtools.com/documentation/api-reference/extracttext